(7dx) Patterning and Actuating Soft Materials Towards Functional Surfaces and Devices

Research Interests: My research interests focus on a science and engineering about exploring the chemical and physical behavior of polymer and block copolymer at surfaces and interfaces towards functional surfaces and devices.

My Ph.D. dissertation with Professor Alexander Boeker at RWTH Aachen University in Germany in the Institute of Macromolecular Materials and Surfaces focused on development of functional surfaces with regularly formed nanofeatures via non-lithographic wrinkling and directed self-assembly of block polymers on surfaces and interfaces. Especially, I aimed to extend the patterning abilities of “soft” block copolymer materials beyond uniaxially aligned stripes or crystal-like patterns into multicomponent or 3D structures. I created templates of complex nanopatterns in a form of hierarchically sequenced dots and stripes that I generated in block copolymer films on lithography-free 3D topographic substrates. This approach exploited thickness- and swelling-responsive morphological behavior of block copolymers, and it demonstrated novel possibilities of topography-guided registration of nanopatterns due to periodic confinement and spontaneous orthogonal flow-fields of block copolymers. I published these works in Adv. Mater. and Macromolecules as a first author.

Currently, I am in my second year of postdoctoral research with Professor Michael Dickey in the Department of Chemical and Biomolecular Engineering at NC State University. I am working on a project to fabricate ultra-stretchable conductive polymeric fibers with a liquid metal core at room temperature. Previously, the ultra-stretchable core-shell fibers can be formed easily by injecting the metal into the fibers. Metal is prevented from leaking out of the fibers due to presence of oxide skin layer on it. In spired by this work, I have developed continuous fabrication of conductive polymeric core-shell structures via mass producible non-woven manufacturing process to be potentially used in electronic textiles, flexible electronics and sensors. I have also demonstrated soft and stretchable microfluidic devices by exploring fundamental study of elastomeric silicones and liquid metals electrode. I have identified and characterized various silicones and modify them to demonstrate stretchable microfluidic devices requiring high tear resistance and high elongation. During my post-doc studies, I have also spent a considerable amount of time to apply for research funding (NWI – Nonwoven institute projects / RFPs -Eastman chemical company projects).

I also have three years of industrial experiences as a Senior Research Engineer at Hyundai Motor Group, where I conducted research on patterning and coating polymeric materials onto automotive glass surfaces to control surface wettability and optical properties. I derived functional films on automotive glasses such as water-repellent layers from fluorosilane polymer via thin film formation. This project resulted in patents for new water-repellent film and the patents are commercialized and being incorporated into the Hyundai GENESIS EQ900 car.

At the poster session, I will present an overview of my past and present research, as well as my plan for future research activities how I will continue to seek fundamental insight of soft materials such as polymers, block copolymers, and liquid metals. One of my long-term visions of research career is engineering the self-assembly of soft matter towards hierarchically structured functional surfaces and devices as means of writing patterns on the nanoscale. I also envision to use liquid metals, which are compelling materials due to infinitely deformable while retaining metallic conductivity, embedded electronics to be implemented in soft robotics, electronic human skin and stretchable energy storage devices.

Teaching Interests: In addition to my research career in academics and industry, I have spent a considerable amount of time developing teaching and mentoring skills. I have served as a mentor to five undergraduate research students during my graduate and post-doc studies. I have encouraged them to devise experiments and interpret data very independently, so one of them is currently writing the draft of the manuscript by himself. I am willing to teach the core undergraduate level courses in chemical engineering and polymer science. At the graduate level, I would like to teach polymer physics at surfaces and interfaces and interfacial behavior of soft matter. I would also like to develop a new course on nanofabrication techniques. The purpose of the course for aimed at graduated students and advanced undergrad students is to teach unconventional nanofabrication methods beyond the conventional lithography techniques in developing surfaces and devices in desired shapes on the nanoscale.